Automatic switch for interconnecting lines



- @www 4 Sheets-SMM EL' F., ALDENDORFF Filed NOV. 28 1913 om omomom ow omomom om om ow owomow om owomom @WOW m. 30, wm

QL 30 M923., y l l .F. ALDENDORFF AUTOMATIC SWITCH FOR INTERCONNECTING LINES.

'L Filed Nov'. 28, 1915 4 sheets-snm 2.

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@un m, ma n'gffmn F. ALDENDORFF AUTOMATIC SWITCH FOR INTERCONNEGTING LINES File Nov. 28 1913 F. ALDENDORFF* AUTOMATIC SWITCH FOR INTERCONNECTING LINES 4 sheets-sheen 4 Wig 4L,

Filed Nov. 2a, 1913 lar fsectioni 'lowing is a specification.

Y '-'short and quick vtion of a line finder. 1-

I PatentedV Oct. Y 30,1A i923, 'l

v STAT-Ese AUTOMATIC SWITCH ronsIn'innconiiincTine LINES.

` ,Application inea November ea-isisfreer'ial No. 803,566.

. (GRANTED miriam THE PROVISIONS or TI'inAcT or traitons, 1921,

To'aZZl/whom; may'uconcem: v 1 Be it known that I, FRITZ ALBENDorner',4

4a citizen ofthe German Republic, residing at 23 .Barbanter-StraSSe, Wilmersdorf, Berlin,

Germany7 `have -invented certainnew Aand useful Improvements in Automatic `Switches for Interconnecting Lines, of 4vvl1ichthe fol My invention relates to machine SYiitch-'p ing systems and more particularly toquick ofY connecting to` any onel of a large group of lines by every movements of the moving contacts or Wipers.

Short movements of the Wipers-are attained by dividing the. contact banks of the finders into sections and arranging the Wipers` to rest normallyjat-a point between y 20 the. sections'so that when a call -is initiated. in any section the Wipers will immediately commence travelling toward that particu-l The` speed of action of the :finders isincreased by` 'constructing them of two switches which act simultaneously the one switch'choosing the-section ofthe contact bank containingv the calling line andthe other choosing'the subsection in that section.

The motionsof the finders are controlled by relays which are in turn controlled by Athe 'calling subscribers. 1 l l My inventln'qwill be fully understoodfrom the following description and by refer- Fig.- 1', .is a diagrammatic representation of the bank contacts and vmovable brushes of a line' finderA andanfillustration.ofthe order in which .,tlie'flines of a-group -are connected to the bank contacts of .thev finders belonging 'to thatv group; '.f

Fig. 2, shows partly in perspective view and partly,diagrammaticallyl Fig. 3. illustrates the circuitsfof -lie sub scribers line and 'cut-offrelays, the;fcoii'n'ections between the subscribers line relays and groups of permutation Wires used for guid-` ing the line finders to a calling line;` .and -the circuits of a finder starter. f f

bers. `For example the lines matictelephone 4i seran-I... isis.)

L* Fi .dand 5, represent the'circuitsnof the line nders, and l l -Fig 6',. hows the circuits or final selector. In Fig. 1.'. are illustrated the ten lrows of. contacts of a'hundred point line finder.v The hundred lines of a hundred .group are connected in the order indicated by the numy numbered from 400 to l09- are `connected to the bank contacts of thefirstrow. The lines numbered 10 to 19 are connected to the -secondV row of bank contacts and so forth. All the lines with units digits ranging from 0 -to 4 are connected to the left half of the contact bank and all the lines with units digits from to 9 are connected tothe vright half oft-he bank. y. v y For eachfroW of contacts there is a Wiper wo' to wn. The line finder is so arranged that of a connector according-.as the subscriber calling is connectedt to the left or right half. of the con- 'tact bank the 'Wipers wo to 109' will move fromtheir `iniddle position to the left or right. TheV furtherest distance thattlie Wipers Will have to travel is thus the dis tance of five contacts.

The Wipers wo to w., lated so that no connection is made to the calling 'line by these Wipers alone. is, however, another Wiper VV-thatis connected to a trunk o r link circuit which co operates with the Wipers too to 109. This Wiper W moves towards the upper or low-4 'erlhalf of the contact bank accordingas 4the ycalling line appears in the upper or lower hal The Wiper lV stops-moving when reaches the Wiper wo to 109 that issituated in the row containmg the bank contactsof thealling line. The greatest number of .rows traversed. by the iviper lV is five. Both the set of Wipers wo to wn and the Wiper W travel simultaneously.- Therefore the Vmaximum time required for the finding of any one line out of a hundred is the time that a lWiper w or-VV takes to move five steps and the average time required is the time needed for 2.5 steps.

A means which may be used for propelling the Wipers wo tO wg' is shown in F ig. 2, in which S is a wiper shaft bearing the are normally insu-V There b. .At the bottom end of the wiper shaft is xedvafdisc. "This d isc d is driven by "another disc d1. or di, fixed to a'driving shaft S1 that maybe common to aflarge-'nuniber of finders or selector'" swlit'chesf'e1 and es' aresolfenoids which. on being energized-by' anfelectric current magnetize their respec-j tive'discs d1 or d, and then'attract theputer rim ofthe flexible disc dto 'their respective dissjfjdl'br d2. v The shaft sfwithjthe discsd, 'and' d2 rotates in the direction "indicated bythe arrow-(a) sothatwhen'fdlis mag-ff -netized' the wipers-wmtow, will rotate. to wards the left-:ofthe Contact bank when d2' is magnetized 'these wipers will be' lrotated towardsl the-right half -oi thecQI'I-'" I tact bank. 4'The wipers wo to *w-g each conf sistfo'ia pair` of brushes of which the upper' one engages with thel contacts "belonging to .thevarious 'subscribers contained in .its par` "':ticularrowand the lowerone slides'up'on a solidcontact"piece'e. g. 77.' Each contact. 'pie'c'ejag".top9 is connected to the fixed Vconcndaryswitchl is constructed like theprimary.. switch just` described 'except that' it hasonly one .row of bankcontacts and one .wiper .W; instead of ten'. The wiper 39 is moved.. by its solenoids or magnets 'l p '1; orf ,"towards its loweror upper' ve ,contactsA connectedt'o the lower or upper -vive ccntactpieces pto pgorpgtop, re-

tact ofrga secondary switch SW. The sectligu'tf attached to a switch de. When'the '-shaftfS'isfrotated in the direction of the arrow@1 the. tongue t slidesup onto the top of' the disc davand causes the switch ds A'to clos'e its top contact'cl, but Vwhen the Ashaft S isturned' in the direction of' the arrowa2 the-tonguet slides down. and rides on the bottom o f the disc d3'and closes the contact 02- ofthe switch ds.' This switch is used whengrestoring the finder to its normal position as will lbe'iully described-later.

. The secondary switch- SWis also provided with .a switchsimilar toda', but this is not shown in Fig; 2. 1

Thev shaft S of the finder also has a cani d, which moves an oli' normal switch OS 5'5 the functions of which will be fully described later.

Althoughfior simplicity of illustration only one wiper 'w and one set ofbank concontacts are provided as shown in thelcircuitv diagram in Fig. 4.

I InFig. 3, S,'S S05', etc. represent. the subscribers stations olf a group-ofone h`un- The. first finder are the inotor magnetsof thel 'and E1, and Elzreprese'ntt e motor Inagoz'theshaft S .f a" discg' dafhaving, an oblique slot Zat its i periphery. Projecting into this slot is a.

dred subscribers. The stations'sio, S64, and

S05, Swrep'resent the first and-ifth and sixth and tenth stations o -the `lrst tens` group inthe hundred, this tens groupbeing connected vvto thefsets o -.bankjcontacts numcated in the` irstrowbfjeaoh'fline finder of' th'e 4h -und'red group.l, For. simplicity/'of .illusie f' tration only two stations' 104,105, aresho'wnl s bank con'tacts.

is represented by four ofgits'tensets of wpers'wol, web "woeawla, mlb; wlcwa wbba' w-'`w.,fw%, wcbelonging to theprimary switch' and' the set of wipers Wbelong'ing to the secondary-switch of the finder. The

primary and-'secondary switches each have an a'ddltionalwiper Wpand Ws. E, and E'2 nets of the secondary switch. of finder F1.' DSD Fig. 5 is the switch corresponding to de, Fig. 2, belonging to-'the primary'switch and D S2 a similar'switch belonging tov the secondary switch of thefinder F1.

uper halves" of the.- w

`shown connected I to' their1- VA Fusi mannheim gr'oiip I rimary switch 'A isan o -normal switch on finder F1. t,"

and '31, are test relays and is a release relay offind'erFrv Therelease relay, con-v order to' simplify the drawing, are shown near .the motor magnets E that they control.

The switches are-'shown in their. normal positions.l When-fthe release relay rZ- is' -enelfgized itmovesthese switches from their,

back contacts to-.their rontzcontacts.

The'iinder F1 is lalsoprovi'ded with a con'- necting relay C; jwhich; extends the line of a callingsubscriber to the neXt switch or mum -traflic.` F2 representsnother finder in the same'hundred group.' as many selector, Fig.j6,'tl 1e'moment the-finder has found the calling. line-.r-f

ofthe parts of ,this 'fin'der are'fshown as are Ws of the primary and secondary'sw-itch of sufficient to make the'system 'comprehensible. -The fgiictionj-'of'thegwipers Wp and' i and W1 to the bank contacts that are connected by wires such as 04, 05 etc. toa call-.-

ing line. The wipersWp, Ws-.will'ther'e-fore 1 be called guiding `wi-pers. The guiding wipers travel over contacts p, lto p, and.V p1., l

to p1, which are connected to .two 'sets-ot permutationwires 0 to 9 and 01 'i,0"91 'the functions of which will be explained "rese,

m'ly 'The bank Contacts'po to 10e an 'Pio 1 Y i i to p1, of all-the finders of a hundred vthe sixth row of bank shown. i

' connected through woa,

group are connectedin multiple to the grou 4s of permutation wires, `0 9 and 'O1- 91.

hundred grou permutation wires. l

Each of' the hundred subscribers of a.-

i hundred group is connected by a set of'mul- .tiple wires such' as 04 or 05 to a set of bank Y contacts in each finder F1, F2 of the group,

these sets of bank contacts being traversed y sets of brushes wa, wb, we..

p The subscriberslines are connected to the Y bank contacts in the order illustrated in Fig. 1.- Subscriber S00 is connected to the first setof bank contacts in the first row,

S0, is connected tothe second set of contacts in 'thefirst row, Si,2 to the third set in first row and so forth. In Fig.4 only the connections of twov subscribers, 04 and 05 in the first row and two subscribers, 54 and 55, in contacts are fully Thc'wipe'rs 10%, wob, 'wlc traverse the first row, wipers cola, wlw/vlc the second row, wipers wia, wb,'w5c the sixth, wipers w85, 10%, wc the seventh row of bank contacts.

.The wipers and bank contacts oi the third,

fourth, fifth, eighth,v1iinthl and tenth rows arcI omitted in order to simplify the'drawin".

.l`he wipers 00%, ivob, to, of the first row arcfconnected by a set of wires w10 to the first set of bank contacts on the secondaryv switch ofthe finder, the wipers 101,', wlm'wlc of the second row to the second set and so forth.

In order to connect a certain snbscribers line, say 4, to a trunk line 'a .7) c leading to a selector, Fig. 6, all the sets of wipers avoa, 10%,' woe-tala, fwh, 701C etc. are turned so as to bring one of thesets of wipers e. g. 10" 10%, 100C onto the set of bank contacts that is connected to the line O4 and thevset of secondary wipers lV is turned so as to 1' connect to the set of primary wipers e, g.

vtor magnet E2, similar to @,Fig/Q, will lswitch towards the lower half.

come into action`and will move all the wipers towardsthe upper half of the bank. the subscribers line is connected to the lower half ofthe bank the motor magnet E1, similar to c1. Fig. Q, will be energized and will more all the wipers of the primary If the calling` subscriber is connected to the half of the` Contact bank shown at the left of the line --g the wipers W1 of the secondary switch will be moved. by the mop` has its own two groups of; the line .w1-.y and tor magnet E?, to the sets of contacts con-i l nected to the wipers wou, wob, @00C-mlm wlb, .'wc, to'wtu, wth, wt., located at the left of Y if the calling subscriber is connected to a "set of bank contacts situated atthe right of the line w-j/ the wiprs W1 will be moved by the'motor magnet 2 that are connected to the sets of wipers w53, wh, ws,- to toga, 10%, w90 located at the right side of the line -y.

The direction ofmovement of the Wipers is thus dependent on the part of the finder contact bank that a, calling subscriber is 'connected to. The subscribers unconsciously determine these directions of movement by means of relays m1, m2, and m1 m12 and by circuits .connectedto/their line relays 10o, 104 etc. 1

The relays m1,A m2 determine the direction of movement of the primary. switchl wipers 100 10%, w"c etc, and the relays m1 m1'2 determine the direction of movement of the secondary switch wipers W1.

All the subscribers with units digits ranging from 0 to 4 are connected to the bank contacts shown vin Fig 4. in the lower half of the bank. 'lheretore all these subscribers are arranged to control by the iirst -lower armature contacts 100 of their line relays the circuit (do) of the relaym, which loses the circuit `of the motor magnet E, and thus causes the downward movement of the wipers ofthe primary switch. n A

The corresponding line relay contacts 100 of all the subscribers with units digits ranging from 5-9 are connected to the circuit UI of the relay m2 that closes the circuit of the upward motion magnet, E2, for all the subscribers with these units digits are connected to the upper half of the bank.

- All the subscribers of the group with tens digits ranging from (l to 4 are connected to bank contacts shown in Fig. 4, at the left 4side of the line y, the 'wipers lVl of the secondary switch are moved towards the wipers m5, um, un, vetc.,'.by the motor magnet E1, which is controlled by the relay m1,.` Therefore all the subscribers with` tens digits ranging from 0 to 4 are connected by the contacts 101 of their line relays to the circuit Z@ connected to-the leftward motion relay m11.

All the subscribers with tens digits ranging from 5I to'9 are connected to bank contacts shown at the right side of line -Ji/ in Fig'. 4. The motor magnet El2 that causes the wipers W1 to travel towards the pri-mary wipers, in the right half of the bank is controlled by the rightward motion rela)Y fm1, and therefore'all the subscribers with tens digits ranging from 5 to 9 are connected by their armature contacts 101 lto the circuit (ra) .of the rightward motion relay m12.

towards the secondary bank contacts' -catewhether the -calling'subscriber is con- Contact bank and..thatlfthe relays022,155,211#2 indiene; whether the samen-ber is in the right or lefthal of' the-bank.-

indicate whatl quarter 4of th? Contact bank the subscriber "is iin-Ifthe 4subscriber is in relays 'm11 and m11 would bejenergized soils I 1 to energize the 'motormagnets E1 and- E15 A 1' The particularline inthe quarter'of the I 1.5 coiitact' bankjindicatedby the relays'l mi, m2,

'i mtl-,m15 is indicated by means of thejfperm'u-v tation wires to 9 and 01 to 91.. "The permutation wires 0 tov 9 determine the point. p5 to p5 at which the primary guiding Wiper .W5 4wire 9 are earthed'by contacts 103and 1021 correspond-to the-tens and unitsA digits -re -cuit at its contact 115 for the 4ritgghtward moshall stop and the permutation wires 01 to, 91 determine the point of stoppage of .the

secondary guiding' wiper Ws. i They ermutation wires 0 tof9 andO1 to 91' spectivelyfof the calling subscribers. `f The I' Contact 102 ofthe line rela-y Z50 of subscriber 00 is connected to theunits vpermutation, wire 0 and contact 103 lof this relay is connected tothe tens'permutat-ion wire 0. The

contacts 102 'and 103 of the subscriberl are connected to tens permutation wire 0 and to -units permutation wire 1, respectiyely,

' Thus the connections between 'lthe permutatations, and each tionwviresfand the line. relay contacts .1'02

' vand 108 of the hundred subscribers are such as to produce one hundred-diiferent permuermutation represents a die'rent combinative setting of the primary and seconda-ry switches of a finder .Fn F2.

' ".Thus `if subscriber 05 calls the primary e. g. No. 59 makes subscriber;

switch ofthe finder will be moved -so as to bring the guidingwiper Wp into connection with the units permutation wire 5 and the i vsecondaryl guiding wiper W1 will be moved `intoconnection with the tens permutation wireO and as the -sets of brushes w05, 10%,

woe- 1015, (wlw/w1, etc. and W1 are moved in unison with their guiding wipers the subf' scriber 05 would be connected through the sixth set of bank contacts that. is connected in the first contact row tothe wires 05l and It will now be assumed that a subscriber When the calling subscriberk S5, removes his receiver from the' switchhook he closes vhis line loop,a5, Z259 in a well known manner and his line relay Z', is then energized by a Currentflow'ving from the negative pola-.0f

i'the., exchange battery throughthe Contact l 110 ofthe finder starter F S, common lfeed wireIll, contact .105 of-line' rela 159,112, fbxs'a'z'a'aa a connection with lanother.

113 to earth, Line relay" 5, isf'enering its contacts 100, 101, 102, 103 andi?y '04.

' Sincejthe-subscriber S59 is connec gizedand'opens'its contact 105 whilstvclhs-` the line the upward motion relaym2 be nergized.in order to setthe finder onto- `the calling line.

connectedjto the circuits w and r andthe relays m2 and'm'lz'are energizedby circuitsfrom the -negativepole of the battery, through FS, m2, u, 100 to earth andfrom'.

'the negativepolethrough m12, ri, -101 to earth. At-th'e'same time the -tens permures ectively.

.armature contact 114 and prepares a circuit for the upward motion magnet E2 andthe rlghtward motion relay' m12 prepares' a' cirhe upward motion relay-m2 `closes l Therefore" the armature thelower left hand quarter for'example theffcontacts-100 and 101 of the line relay Z5, are

. eo'- l tation wire 51 vandthe units permutation'ffv tion magnet'Elg. -The finder starter'F S is energized' in series with. .the relay m2 land4 by attracting its armature .116: momentarily closes the' contact 117. This causes a current f .impulse to fiow from the. negative p ole" through 117 ,starting wire S t', contacts 118,

119 of the oi-nOrmal'SWtChof the first idle finder (e. g. F 1)., wires`123 and 124, magnets a il', u1, contacts 115 and 114. The magnet and El., cont-acts 128 2L11d. 132,-W1'es E15. is energizedy and moves the wipers W1, .1.

WV, of the secondary switch one step towards the right hand wires w15, wle and thefmagnet.

E2' is also energized and moves thei'wip'ers w05, 10%, 100e-w1., wth, 101e, etc., and Vftheguiding wiper "Wp' of the primary one step upwards.l

`It will be assumed move their wipers by a step by step ratchet i 'and' pawl device 'so that for each impulse sent vthrough these magnets'their wipers are moved to another set of bank contacts.'

Itl will .be noticedtha-t' two magnets 'E1 and E'are connected to the wire 123 and two magnets El1 El2 to the wire 124. The" impulse sent from the finder 'starter F S over the starterwire Si will, however, al-

ways affect one of the magnets E1 or E2, and

nia'm'zsmlifme;`V i On theV primary switch 4of the finder vbein one .of the magnets E11 01512121 only, because there will alwaysbe onlyr one circuit `of-each4 f pair of motormagnets .closed by the-'relays 1210 g 119,. The primary switchis'a'lalged'toexef 1 cuteits initial: 'movement when the starting impulse over .the starting wire Sg.

10 pole through 13 3, 134 tothe Wire 138. From', throughl the.

- that the Contact 121 through which the starting wire is extended to the next finder F2 is not. closed before the starting impulse ceases and a false starting of the next finder F2 does not occur.

When the contact 122 is closed an inter-- rupter 1133 is connected to the motor magnets in place of the starting wire and cur-l rent impulsesrhen'flow from the negative the wire 138 the impulses flow wires 139 and 140 to the @nly the circuit o f one magnet in each pair is' closed bythe relay y m1, m2, 71111m12 'atI any one time. In the QU'cnly the magnets E2-and E12 causingthe tively,

'ease 'assumed the 'circuits yof magnets E2 and E12 are closed at 114 and 115 respec Therefore the impulses flowing throughthe' Wires 1,39v and 140 will energize Wipers of the primary andsecondary "witches to-be both moved upwardly as I shown in Figure 4.

` upwardly and viceversa. Y, l

In th'ecaseassumed the Wipersl VWi'wilh 1 @will move downwardly, or that the pri ary lswitch will, 1nove -its Wipers downwardly whilst the secondary switch moves itsvyipers move upwards one step andthe. circuit of the magnet E12 jill then be' broken by the energization of the secondary test relay sp, for a circuit will be established for this'v relay by the secondarv guiding wiper Ws reaching the tens permutation wire 51. Thislcircuit c may be traced from the negative pole to earth, lOne the energizati'on of relay 8p the circuit ofmagnet E12 is broken at 136 andl the motion ofxvipers W1, Ws is'stopped. The Wipers of the primary switch will continue their movement until the guidingy wiper 7p-reaches an earthed permutation wire, which in the case assumed ,Will be when the pern-lutaticn Wire p9 is re'ached.- The circuit of the primary test r lay Willthen be closed. from the negative/pole' through 141, tp, Wp, p9, 144, 102 to earth, andthe test relay ,tp Will open the circuit ofthe magnet E2 at contact 135,/ thus stopping the operation ofthis magnet. The Wipers w52, 1051,. w, will now be resting. on .the set of bank contacts 17059 to which subscriber SBP isconnected, and the set of Wipers W2 -Will be resting onthe secondary switch 4contacts Connected by w11, to w52, wh, w52. Thus the" calli'ngr'l-ine 'will bel connected through its Wires 59, 6059, w52, 10%,; w52`-'-W15, W1 to the trunk abc. Y l f' The moment both ,test relays sp, tp are energized, a circuit isvelosed from the negay tive'pole through 137 145 C R to earth and the connectin re'lay R then closes its contacts 146, 141iZ 1t may of course'happen ythat both switches` ,148, 149 Whilst openingits contact v134. By the closure of contacts 148, 149 the calling line is extended to the selector Sel and the clsure. of the contact 146 results in the energization of the calling subscribers cut offk relay cojq by a current .from earth. through C R, 149', 146, c, middle brush of W1, 10152, bank contact of line 59 on which in, is resting, Wire cyconnected to this bank contact, cut ott relayco;L30 'to the negative pole of the battery. vThe 4cut off relay isenergized and cuts the line relay l5, olf of the callingline (122,622, thus deenergiz- `ing the line relay,

As long las a linerelay is energized the upward motion relay m2 or the downward motion relay mv1 will be energized 1n series vwith the Afinder starter'and the finder starter will keep open the common battery feed 111 to all the line relays of the hundred at 1'10 and thus prevent any other subscriber in the group from calling. But 'this condition only lasts until a nder F1, F2 etc. has made a connection 'with the calling' lline and as the average time'required for thisis the` time.-

that it takes the wipers to execute 2:5- steps lthe blocked condition of all the lines except the first one to sendein a call only lasts a fraction of a second and a second subscriber sending in a call Would not notice.' any de- When the line relay Z5, of the calling line is deenergized .by the energiz'ation of.

the cut off relay 0052 it opens its 'locking circuit contact 104, the circuits of the motor magnet control relays m2 and m12 and the earth connections or the permutation Wires 51. and 9. The nder starter F S is ,also deenergized and the common battery feed 111 closed at 110. The 'falling oli' of the armature ,116 d'oes not cause a. closure of the starting circuit at 117.

The opening of the earth connections of the permutation wires 51and 9 resultsin the deenergization of the test relays si) and tp and 'in the closure of the motor magnet circuits at 135 and 136, but no operations of lthe motor magnets is possible because their l,

By the closure ofthe contacts 148, 149 the 'line control relay L R is connected to the calling line S52 and is energized in a circuit including the calling subscribers line loop. This circuit is from the ne ative pole of the exchange battery through t e lower Winding 10%,@ s, a, 148, al, upper wlndlng of L R, to

earth. Y If the calling. subscriber *desires aconnection with subscriber No. 7.8 he will by means of his. selector. controller first cause 'seven y openings of his line loop and then cause eight such openings.- Until the calling sub# scriber commences working his Selector controller-the linecontrol relay Ly R remains energized and closes'a circuitfor. the release relay R R from the negative. polejthrogh 156, 180, R R, 181,176,18210 earth. The

sevenrapidopenings -and closings of the line I control relay circuitl result in seven openings of the contact v17 6 and the change over lay G R, -is thenI energized .by a current',l

from 'the' negative? poleof the" battery .I through 156, R R, C to'earth. The relay",

LR' is'so adjusted that duringjtheoscilla-i tionsof its armaturel the-contactsflf and- 176 are scarcely .closed and if theyare closed at all the' closures are of. the shortestA possible duration. yThe relays R R''and'nfGR are thus'maintained energized whilst' the-fee. 4lecting 'impulses are' iowing..'1`he contact,-

" 174' is 'so adjusted as to be closed during .a

considerable periodof each oscillation.

'so Each time the Contact 174 is closed a currentimpulseows from the vnegative pole tlhiough 156, 174, 171,178yertical magnet .V M of A the-selector Sel, .which is'ass'umedto be ofthe .well knownv up.. nd around'type,to earth. The wipers 'of the selector are' thus stepped up to'the'seventhvrow of bank contacts.- A

' pause now ensuesv during which' the lineI control relay pulls up its `armature steadily and short circuitsthe change over relay that the' closure of 177 'results in-a currentthrough .156,"174, .184, 171, 1118, R M," toearth. -As the .calling desiresconnection with the "e i'ghthsuhscriberin the #seventh contact row the wipers/wsa, uzsb, wspare stepped. round eight steps and then 'rest' upon line No. 78 whi 6.9: similar .to 'amj1255,.,c,' leading to the desired'` T' subscriber No. 78.1 When the pauseensues `'z`a.. fter tl1 e second series vor' impulses the change w65.. bytheshort circuit 'at contact'17eand the x side switchmagnetis again energized by a @verrelay CR1 isagain` dcenergized -iciently to'preyent the test relay .of an` C R' causing this to release its armature 177. Thel o1"nor`1nal contact'172 is closed "when thel selector executes its 'ifi-rstupward step so" h is'connected to'wiresr current from the .negative pole throughll, i 173, 183,177,172 to thel side switch magnet S1 M- and earth; The side switch .now changes over the rotary magnetfcontrolunction to the testing function vby closing-the test circuit from earth through the'switch arm 179,

160,v 190, wsa, 0,8, 'cut-Av off relay-co78 `(notshownfbut sirfnilato 0055) tothe negative pole'. 'If the wanted line Vis free the test ref lay 190 `will receive-sufficient current to en-v ergi'zeit `and .will 4closeJ its armaturecontacts By closing its 4contact 165 it short"circuits a part .of winding and re. d uces the potential onthe test Wirec78s11f other. selector that maytry-to maken.' con nectionlwith'thebusy line from attracting! "itsarmature.' The-fclosure f. the. test' relay Contact .164i y causes the 'applicationof theringing Inachine SR1 M 'to' thel wanted. line-so that `ring-- ingcurrentliowsfrom .earth'throughltI M,I

ringing control relayR1 411,164, 169,.'wea,

` am, wanted subscribersfg'bn, weh-3166', inf-j terrupter 192 to the negative pole;v u

When the called subscriber responds by removing his receiver .from the switchhool' the ringing current flowing vthrough .relay R1 R isstrengthened sufficiently to energize it, so thatit closes its armature contact 163 and. energlz'es a relay 193. bya current from earth through163, 193 to the -negativepole The relay 193 then opens the ringing cur-l .ren't circuit at. contacts 1'69, '166i and'conim;

nect's. the calling and calledlines together at contactsg168, 167 ,so that the conversa# 'tionbetweenthe two subscribers may no w take place.V

When'the-subsciibers replace .their receivf f `I 5 line'floops the linecontrlirelay LR is d ee'nT ergized` and. the shortzcircuiting contact of .the release relay RR is permanently closed. The releaserelay'then'allows its armature Vto'fall :back andcloses. its armature coners on ltheir 4switchhooks. and thus open theirtact170- whereby-'the release: magnet Rel of the4 'selector Sel isa-"energized in. a circuit.A i from the 1 iegative`-pole'-through'- 170, Rel,v jl. "off nornrialf4 contact -161wl`1ich was closed when 'the selector executed its first movement,to earth.v This-circuit remains closed until the"selectorjhas.regainedits `normal position..- f-

1.- f The release.v magnet inadditio'nto releas- `in,z,the selector Sel opens its test circuitat 160 andthus preventsthe applicationoi test potenti-al, to .linestouched4 by the wip. ers I wsa, wsb, wsc,duringgthe restoration The release --magnet also closes contactsl58, 159. '.By the closure.' of 159 the 'connecting relay-CR is short f f circuited and the contacts 146, 147,148, 149

are opened and the relays co5', and 155 deof the selector.

energized.- f e By the closure of 158 the 'release relay' of the line finder is energized by a current from earth through 158, TZ to the nega-tive pole. The release relay 'r'Z closes a locking circuit tor itself from the negative pole through rl, 157, 120 to earth. It'opens the battery connection to the finder test relays sp, tp lto prevent these relays from acting ,during the restoration of the finder toits circuits of these two magnets will be 'closed because the directionl OtfinOvementof the" primary and secondary switches v was suchas to cause the closure of the. contacts QC,- -and C12 of the switch DS1 and DSZ', which'.

he switch @Z8 in Fig. 2. i

Therefore restoring impulses willtlow it will be reinembereda're constructedilike from the negative pole .through 133,?"122, `iai, 138,135, 139, E2, 02,1331@ earth and.

from'the negative pole through 133,- 122,

134,138. ies'. 14.0, E12,.o12 Ds2 to garni.'

lVhen the primary and secondary switches ot the finder reach'. their normal 4positions theswitches DSlfa'ndlDS2 assume.

.their middle positions'iirwhich none of their contacts are closed.. The ottnormal switch USl will then 'also have 'opened its contacts 122, 121, 120 and closed its contacts 11S, 119. Thefopening of the contacts of the switchesv DS DS2 results in the primary and secondary switches of the finder stopping intheir normal positions and the opening offtlie. contact120 causes the release 4relayv'lto be deenergized and the circuits of the motor magnets E1, E2, El1 and El2 to be reconnected to the wires (lol,

u, Zcl and ril controlled by the relays m1,V

' The finder F, is now ready to l'c used for another call.

As lonU as the finder F is not in readi-A switch tor connecting a line in one. otsaid groups with a-pledetermined line in the other group, means for moving said switch in a certain predetermined direction to connect certain ones of said predetermined lines, and means for moving said switch in another direction for connectingr with ccrtain other I iredetern'iined lines.

2. A group otlines, a switch movable contact, a lixed contact tor each ot said lines` said contacts being arranged in sections. said niovaible Contact being :Lrranged to be moved in vthe'act ot making a connection with a line in the direction towards one section of contacts and in the opposite direction towards another section of contacts.

. 3. A group of lines, a switch having a bank ot contacts each contact being connected to a'said line, the bank of contacts being divided into sections, a movable Contact in said switch, normally situated between the said sections, a magnet for driving the movablecontact 'towards one sectionot bank contacts vand another magnet for driving the movable Contact towards another section of. bank contacts in theact ot making a connection-` 4. A switch having a line inf-one`- directionfand into two sections with the dividing line'i'n a second direction, a movable contact capable'ot moving in the one direction towards one ofthe sections with vthe dividing line in the one direction and capable of moving in another direction towards the other section with thesame dividing line.I and anotheninovable Contact capable of moving in the one direction towards one ot the sections with the dividing line in the second direction and capa-ble o't` moving in another direct-ion towards the otlier section"with the said dividingr line in the said second direction.

5. In a switch, a .bank of stationary contacts, differently designated lines terminating in said contacts, movable contacts cooperating with sai-d stationary contacts, means for moving saidmovable contacts in 1dilferentdirect-ions to connect with the stationary contacts ot a line, and means dependent on `the designation of the line to be connected 'with for determining the direction of movement of said movable contacts.

6. In a switch, a row ot' fixed contacts, a movable Contact normallyv rest-ing yin the middle of said row of-tiXed contacts', means for driving'said movable contact-trom the middle otsai'd row lin one direction, means for driving said contact tro-m the middle of the row in thc opposite direction` a second row ot' fixed contactsLa. second movable contact-'normally resting in the middleot said second row. means 4tordi'iviiig the said sec' ond ino-table contact in one direction, and inea-lis for driving said second movable contact in the opposite direction'.

'7. ln combination, a pluralityot subscribers lines, a line finder havinga plurality of stationary contacts in whicliaid having `a soI bank Lot' contacts divided into two sections with the dividing by said lines, la switchhaving -'aglo'ankfnoi. contacts divided intol section s',fa movable :contact normally resting' at' a' point between?. vtwo said sections, ma 'ets fordrivingsaid movable. contact in 'dlii'erent directions telf" lines terminate,I nriovaljle contacts for finder', means responsive to the 'initiation ot a call fon a certainl'ine' formoving said 'contact's .over ltlr'e stationary contacts of certa'uf1-4 predetermined -portion of .said lines includ-.-

ing the callingl line,- and means .resposive to n the 'initiation of a "callon lanother .line "for movingeaid movable contacts over the staf" tionarycon'tac'ts 'of'.thevhalanceofthelines, Y I .lo I

including 'said ctlier'linef..

'eachjhavixig Aa movable" contact, a. 'fixed con? forf'each 'of said lines, `saidcontact's be'f. inglrangedin 'sections, said movablefe'on'; tact ybeing'arranged''to be moved in the act of-" making'a' connectionwithra line initiie- 'direetion toward one section of contacts and `S tiation'l ofA a' call for' actuating 'contacts' of I' 1in-the' 'opposite direction towards another'-l Section of vcontacts:A

two contacts andI a-'plu'rality of condmtors,

' means .for operating onecontact tof connect; a calling line with' a conductor, and-Iman# i for operatin the'fotherie'ontact' :for- .oon-f.

nect'in a con notor :with 'an idle trunkline.'

10. n .a telephone;- exchange;system,faj plurality of 'subscribers"' flines, fa plural-ity; "df trunk'. lines, a switching devicefcompris. .ing ltwo sets 'of contacts anda pliirality' of.

conductors', means yo'peiativej-Jnpo n the' fimvone s'et to conn'ectthe callingfline with .a con` ductor and simultaneouslyA 4operating' 'conetacts of 'the other' setio'r` connectin'gfau idle j trunk line .with `said last mentioned'iconj ductor.v

11; A gmp-ef-iies, a'. plurality' bf, switches each hai/ing' a bank. of contacte( each contact being 'connected to a-said line,

l the 4'bank of contacts being divided-into-secnormally .resting between .-"two" sections, a; magnet' ord-riving the l movable "contact tions, a movable'contact on eachsaid'switch-` towardsA 'one 4'section 'o'.f-4 bank contacts and another magnet :lor driving igthe; movable contact towards' another section'o bankc'ons tacts in the 'act of 'making a' conr'xection;V i

12. A group of lines, relays" controlled' wards said sections and' controlled by said, relaysl 1 3.- 'A

tact'sfdivided 4into sections, movable contacts normally resting atpoints between sections, magnets `for driving' said movable; contacts in different directions.towardssaid sections4 and controlledby'said relays. -'14.- "A"groupof lines, relays controlled 8 1 A' xgroup of lines, a.plnrality"of 'E ofV lines, "5 by said lines, a 'swtchiliaving banlsof con*- by said lines,. a` plurality of-switcliesiea'ch *having banks ofcont'acts divided-into. sec.-

tions, 'movable contacts .normally resting vat j points' between sections, vIlflagnets'for driving saidl movable contacts in different directions towards said sections and controlledby'= s aid by. the said? relays,` means for. "cau'sngf a switch i tof' connect only. t0' the line from which' it received the starting inipnlsfe.- 1 1551A, switch comprising aban'ktof contaetsdivided into sections, a movable contact'jnormally resting between'said sections' l-Inf'zansi for 'movi' fsaid 'moVable'contaettof `wa1jds one. of s ai sectionsmeansior m'ov-A 'fing said .movable contactftowardsanother of said'sectionsa'nd means for stopping said movable' contact .on a `contact-in' aL said lsec-v 'a i t tion. "if 16:- Av

ta'c'ts divided into sections-,a movable contact normally resting. be'tvveenfsaid sections, means formovin said movable 'Contact tow'ar'dsone-of sai sections, means formavin'g said movable contact 4towards 'another roup- Of'ilines', a plurality '.o 'switches' each' comprising' a bank. of con-* of 'saidl seetions and".means' for. stopping .A 'group of" lines, .relays controlled'. y Sa1d;lines,a switch comprising a bank of f contacts divided` into sections, a movable vsaid'movable.contacten a'contact in a said contact' normally resting' between said vsecjv tions, means controlled'by'said' relays .for- -4 movinggsaid movable contact towards one 109,1-

of "said sections, means. controlled by said. l

relays-for moving-said movable-*contact totion;

@wards ariotherfoffsad. sections'can'd f'means controlled by said relays for stopping. said."' mo able. 'contact-, on -a contact in a sec'v l fr'18.-`A of. lines,

'controlled movable-"contat -tacts divided into; -sect-,i(n 1s 'a'lmovable contact normally resting between said'se ctio1 1's, means or movingIsaidmovablecontact'towards 'onefpfs fz'sectionslin the act" of '(1 connecting, means-idr moving said movable bcontact towardsantherfof said's'e'ctions in the act; of com iectnng' and restoring means arrasar for. moving' the movable contact in the-same. direction 4whilst restoring as 'it did in the actwo'f connecting. "20." A group'of lines, a plurality of switches each comprising a bank of contacts divided into sections, a movable contact normally V resting between said sections, means for moving said movable contact towards one ing av switch to connect only to the line of'said Asections in the act otcoiinecting, ltll 'Wards another of said sections in the act of connecting and restoring means tormovmeans for moving said movable contact toing the movable contact in the same direction whilst restoring as it did inthe act of connecting, rstarting means for starting a switch bythe said relays, means for causfrom which it received the starting impulse.

2l. A switch comprising a bank of con-4 tacts divided into sections, a movable contact normally resting between saidl sections, means for moving said movable contact towards one' of said sections, means for moving saidv movable contact towards another ivards another of said sections and restorby said lines, a switchcomprising a bank of contacts divided into sections, a movable contact normally resting betweeiisaid sec- 45 tions, vmeans controlled by said relays for movingr said movable contact 'towards one of said sections, means controlled by said relays `for moving said movable contact toing means for causing` one of said moving means to movethe movable contact into its normal position. i

24.,.A group of lines, relays controlled 'by said lines, a plurality of vswitches. each "5g .comprising a bank of Contact divided into wards one of saidA sections, means for moving said movable contact towards another of said sections and restoring means for causing one of said moving means to move the movable contact into its normal position,

starting means :tor starting a switch by the said relays, means for causing a switch tov connect only to the line from which it received the starting impulse.

23. A group of lines, relays controlled sections, a movable contact normally resting between said sections, means controlled by said relays for moving the said movable contact towards one of said sections, means controlled by said relays for moving said movable Contact towards another of said sections and restoring means for causing one of said moving means to move the movable contact into its normal position, starting means for starting a switch by the said relays, means for causing a switch to connect only to the line from which it received the starting impulse.

25. ln combination, a `plurality of telephone lines, a switch in which said lines terminate in a certain order, means for operating said' switch to select `a-nd seize any one of said lines when calling, means for restricting all selecting operations of said switch to a relatively small number of lines but always including the calling line.

In witness whereof l' have signed this specificationv in the presence of two 'witnesses.

' FRTZ LlDlEND ORFlF.

Witnesses:

HENRY Heisman, WALDEMARHAUPT. 

